Building a slant for torque

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Just over 8 million slant sixes were produced during a span of over 2 decades...doesn't sound very unique to me
how many ford 300s and stovebolt chevys were built in same time frame???? how many /6's been halled off to the scrap man??? yeah in todays world id say there unique!!
 
If you're not supercharging, you're leaving torque on the table.
Seen a few guys over here using the Toyota SC14 superchargers on slant sixes - seems to wake them up a bit, the Eaton M90 might also be a good option.
 
triple weber 40 dcoe running 34 mm chokes, and a set of sensible bore headers (not huge you want high exhaust gas speed back to the merge) that merge at the rear passenger footwell.

that will help bow the torque curve out on the lower rpm side, some what, regardless of what you do to the rest of it.

if you rebuild it i'd use a dynamic CR calculator to assist with cam choice and decking/head skimming for static CR. keep the standard valves port size, a great big huge port is for high RPM/BHP and a smaller narrower one with webers keeps air speed high and makes the most of their ability to atomise the fuel.. superlative mixture at low rpm = more torque
port on port induction means mixture prefect for the cylinder who's vacuum created it. no distribution issues, no big plenum of wet globby mix at low rpm, no puddling of accelerator pump shot on plenum base, acelerator pump shot direct into hot port, file and angle pump jet mounting to get a fuel spray on the bench out the middle of the inlet manifold port for each cylinder (most applicable for the middle) ... etc etc etc.

chevy dude, (below link) but relevant and his little programme for download at the end takes all the maths out of it, if you have the figures for your motor to hand
aiem for DCR of 7.5-8

Dynamic CR

you'll be able to tow a plough up a cliff.... :)

Dave
 
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how many ford 300s and stovebolt chevys were built in same time frame???? how many /6's been halled off to the scrap man??? yeah in todays world id say there unique!!
You should see how many people stop and just stare under Vixen's hood at these cruise ins we're going to. It's like they've never seen anything like it. I bet some of them haven't.
 
Just over 8 million slant sixes were produced during a span of over 2 decades...doesn't sound very unique to me
He didn't state they were scarce or rare. The Slanty IS unique. Only domestic inline 6 not standing straight-up, preceeded every Kraut-wagon that didn't, and are the only one to come with an install package for hotrodding from the factory. It's only domestic rival would've been the Yenko Corvairs, THAT is unique.
 
He didn't state they were scarce or rare. The Slanty IS unique. Only domestic inline 6 not standing straight-up, preceeded every Kraut-wagon that didn't, and are the only one to come with an install package for hotrodding from the factory. It's only domestic rival would've been the Yenko Corvairs, THAT is unique.
the slanted installation of the slant six may be unique, but the engine itself, is not
it was the base engine in how many cars?
forklifts, generators, boats, combines, welders even irrigation pumps

and even IF it were unique, try selling one
there is a reason you dont see them often at car shows

unique_forks.jpg



now, if you want to keep your slantie because you want to, thats perfectly fine
shoot, run one because they run forever, or because no one wants them and you can get them for free on FABO all the time

but dont try to church it up
 
the slanted installation of the slant six may be unique, but the engine itself, is not
it was the base engine in how many cars?
forklifts, generators, boats, combines, welders even irrigation pumps

and even IF it were unique, try selling one
there is a reason you dont see them often at car shows

View attachment 1716060268


now, if you want to keep your slantie because you want to, thats perfectly fine
shoot, run one because they run forever, or because no one wants them and you can get them for free on FABO all the time

but dont try to church it up
LOL!!! I don't have to "church-up" anything, and I also don't have to run around inserting My ego into a thread where I don't have anything useful to contribute in. Take Your "unique" pissing match with DWB, and Your "Forums" pissing match with RRR, and go burn a fat one. LOLOLOLOLOL!!!!! You know, somewhere other than the "Slant 6 Engines" section under the heading of "Mopar Technical Forums", LOLOLOLOL.....
 
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He didn't state they were scarce or rare. The Slanty IS unique. Only domestic inline 6 not standing straight-up, preceeded every Kraut-wagon that didn't, and are the only one to come with an install package for hotrodding from the factory. It's only domestic rival would've been the Yenko Corvairs, THAT is unique.
It's also the only......OR one of a VERY FEW engines that the car was designed AROUND.
 
the slanted installation of the slant six may be unique, but the engine itself, is not
it was the base engine in how many cars?
forklifts, generators, boats, combines, welders even irrigation pumps

and even IF it were unique, try selling one
there is a reason you dont see them often at car shows

View attachment 1716060268


now, if you want to keep your slantie because you want to, thats perfectly fine
shoot, run one because they run forever, or because no one wants them and you can get them for free on FABO all the time

but dont try to church it up
The free and cheap days are gone, because the slant 6 is enjoying a resurgence. I cannot find one anywhere near me that's not 350 bucks at the very least......and that's for a core that "ran when parked" or a rusted up POS.
 
I have one I'd make ya a hell of a deal on, and it would rev better than what you have now, out of an 85 pickup. Put the short block with a peanut head ( have an extra of those as well sitting here) and lose a lot of weight along the way... But Illinois is a bit of a drive from GA.... But I'll give ya a screamin deal.... Only time it got wet is when I power washed it.... Only $349.95 (haha); yes it ran when pulled, been stored inside my heated garage since it came out. Last started it less than a year ago.
 
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The free and cheap days are gone, because the slant 6 is enjoying a resurgence. I cannot find one anywhere near me that's not 350 bucks at the very least......and that's for a core that "ran when parked" or a rusted up POS.
don't tell that to all the old farts around here. everybody thinks it's still supposed to be 1983 prices when they're buying and current pricing when they're selling.
 
don't tell that to all the old farts around here. everybody thinks it's still supposed to be 1983 prices when they're buying and current pricing when they're selling.
Pretty typical.
 
don't tell that to all the old farts around here. everybody thinks it's still supposed to be 1983 prices when they're buying and current pricing when they're selling.
I would have been one in '83
 
I had to buy a whole car to get a Slant 6. Twenty years ago I gave mine away. It doesn't matter how many they made, it matters how many are left and in that regard....no so many.
 
Isky .436 lift cam, headers, 2 brl iron or dual single offy aluminum, 9.1 comp or 8.9.. somewhere in the realm...good tune...small convertor...some head work.
I'm always interested in what folks have done to squeeze torque out of a 225 slant. Please feel free to offer your knowledge here!

@Jim Kueneman, in the Peanut Gallery Survey thread, you noted the following:

Too bad you left Az you could have driven our Dart to see if that what you would want. Rusty and I just got a simulation model of the 225 that seem very accurate we could run with different components and relate to mine. Ours is 100% max torque build from 3500 and down and the model shows it.

What are the details on your build to get max torque up to 3500 RPM?
 
Does any of the cam grinders make an RV cam for the slant?

My philosophy on head porting on the street for the slant is port match the intakes to the gasket. Don't touch the intake. Allegedly it creates a small amount of anti-reversion/minor ram effect. I read that many years ago in reference to V8's in a gearhead magazine.
 
I'm always curious as to why people still even build those things.....
I like something different. I do not buy into the "just throw a LS in" school of thought. Yes they make torque and thus HP. But a lot of modern engines do also. The LS are probably less expensive.
Now a slant is probably original to the car. There is nothing else like the sound of an inline six with dual exhaust.
I would consider a replication of the Hyper Pac for the slant. 10:1 or 10.5:1 pistons, port the head with a bit bigger valves, a bit of a cam, the repop intake and an Edelbrock 500CFM AVS2 carb and a 6 into 2 exhaust header.
When porting the head, I would seriously consider 40° exhaust seats to aid low lift flow with restrictive ports. 225's are not a high rev engine for the most part, so I would be looking at 1.5" primary header tubes. You want the 4th resonant low pressure arriving at the almost closed exhaust valve, to create a low pressure in the cylinder/combustion chamber at the time the intake opens.
There are also resonant frequencies in the intake ports. Tuning exhaust length and collector length can get these to work together, to enhance torque or broaden the torque curve.
Look to UTG for inspiration. For street use a slant can be a fun driver and get good fuel economy.
For a less expensive intake, search for a Super Six 2 barrel intake that was factory installed.
 
I'm always curious as to why people still even build those things.....
I always wonder why V-8 owners enjoy trolling on the Slant-Six forum. I own 3 1960's Mopars with slant, small-block, and big-block engines. I love just looking at the slant, which is a convertible which will always be rolling slow and cool. I even own two 1980's M-B diesel cars just to tic people off. Fuel with bio-diesel (buy at pump in CA) so less net-CO2 emissions than any battery car.

Re the question, I'm waiting for better e-motor boost systems. Seems a simple way to overcome the poor breathing in slant heads, without the complexity of a turbocharger or supercharger. Current ones ~$1000 actually work, but the controls are crude. Costs will come down and probably better controls to control pressure output. You don't want to overboost at low rpm and risk melting pistons. If an EFI system with MAP sensor (for boost, to not clip signal > 1 atm), fuel should properly adjust. Perhaps the company now making an MPFI intake manifold for the slant will someday add an option for e-boost.

OE manufacturers might someday change to e-boost, allowing leveraging them at junkyards. But, I'm guessing the transition to hybrids will limit that since the e-motor already provides torque when needed, and especially in plug-in hybrids where the gas motor is used mostly as a generator. Another thought is adapting the small supercharger in 2000's M-B Kompressor cars, which might be a good fit to a slant. I've seen used ones inexpensive on ebay.
 
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I'm still holding out hope Edelbrock has pitty on us and makes an aftermarket aluminum high compression head, cross flow Hemi would be awesome because you could run much bigger valves.
 
I lost my last slantie in a bad trade, but I had milled the head .15", had nice long tube Hookers, aluminum 2bbl replead with porosity issues, Mopar electronic ignition, it would fry a tire just fine in my D100. Want another just to play with, have a few M60 and one M90 blowers which would be perfect.
 
Does any of the cam grinders make an RV cam for the slant?

My philosophy on head porting on the street for the slant is port match the intakes to the gasket. Don't touch the intake. Allegedly it creates a small amount of anti-reversion/minor ram effect. I read that many years ago in reference to V8's in a gearhead magazine.


I don't think any cam maker refers to anything they have as "RV cams" anymore. There Are a few out there that would fit that bill ...
I had my original cam reground into what is considered a pretty good "RV cam". I keep thinking about adding a small turbo to it once it's all broken in, N/A style, first. Probably no more than 5-6 lb at max boost......right now adding AC to it, gotta see how that + a small turbo play along with each other on the driver side of the motor....

Hey Rug, what ever happened to ya? Don't see ya around on the forums like I used to.
 
Hey Rug, what ever happened to ya? Don't see ya around on the forums like I used to.
Career change. Went to driving trucks. Had to go over the road for 15 months. Duster hasn't moved since 2009. I have a D350 CTD that sat since 2011 or so. It's back running sort of driving. It has a fueling problem. I am thinking it's the injector pump. I bought a used IP and a bunch of extra stuff from a '92. I have bigger injectors, bigger turbo, 4" exhaust, all waiting to go on it. I need to get the IP sorted out (I think) most people on line are guessing with these diesels. I did change the governor spring to a 3200rpm, and did a THD +40hp fuel pin.

I popped onto Moparts the other day. No help there in the truck forum.
 
So I jumped on the forum to update my build thread and saw my name was posted here and had to drop a message in. I will follow up later and read thru this thread. For those who are interested, my build thread is Jeep 4.0L in 1969 Barracuda which is what Killer6 provided a link too earlier.

BTW: As I will be posting in my build thread, I am 1 step away from starting the engine. Final parts are coming. I will post details on my thread by tomorrow night.

As far as the Slant Six, I love them. I had 13.9 second 1/4 mile with a slant six, a Dart Sport man 3sp running I think 3.23 or 3.55 gears.

I will be back tomorrow
 
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